DENTISTRY

the profession concerned with the prevention and treatment of oral disease, particularly disease of the teeth and supporting tissues. In addition to general practice, dentistry includes many specialties and subspecialties, including oral surgery, prosthodontics, periodontics, orthodontics, pedodontics, and public health. profession concerned with the teeth and their associated structures such as the jaws and gums. It includes the repair or removal of decayed teeth, the straightening of and adjusting for proper occlusion of teeth, and the design, manufacture, and provision of false teeth and other prosthetic devices. Origins of the treatment of oral disease are found in the ancient civilizations of the Middle and Far East. Until the 18th century dentistry was concerned only with the removal of teeth, and then only because of pain. Originally teeth were pulled by barber-surgeons, but by the 14th century there existed specialist tooth-pullers called dentatores, especially in France, where dentistry was more advanced than elsewhere in the world. In the 19th century the lead was taken by the United States, where most of the specialized equipment for dentistry was developed. Early dental drills were hand-operatedthe dentist twisting the bur between his fingers or turning a handle with one hand while drilling with the other. Later, a treadle-operated model was derived from the sewing machine, and in 1870 the electric drill was invented, though it was some while before the supply of domestic electricity brought it into universal use. It remained until ousted by the air turbine (high-speed) drill, developed in the 1950s. This has speeds around 400,000 rpm, allowing easier tooth repair with less discomfort. Anesthesia and analgesia were introduced at the end of the 19th century, first by using cocaine or nitrous oxide and later other drugs. Another improvement in the practice of dentistry was the development of X rays, which revealed the condition of the roots of the teeth and any associated decay or infections. False teeth were fairly common by the 18th century, but they were generally unsatisfactory; the impression of the jaw was made using plaster, which had to be chipped off painfully and pieced together again. The resulting denture was made from wood, ivory, or tortoiseshell, with teeth of ivory or porcelain, but was usually a poor fit and therefore uncomfortable. Improvements came first with the development of wax and then plastics for impression taking and, later, with the introduction of rubber and then plastic as the base on which the false teeth could be set. Also, early dentures had prongs or wires to attach them to the jaws, but they nevertheless were wobbly; almost all modern dentures use the capillary action of water to hold them in place, and this requires that they have a precise fit. The technique of permanently implanting false teeth in the gums became popular in the second half of the 20th century. The other major developments in dentistry have been (1) oral hygiene and brushing for the prevention of tooth decay and gum disease, (2) the use of fluorides to make teeth resistant to decay, and (3) the development of orthodontics (tooth straightening.) The first dental school was founded in Baltimore in 1840. Now most countries of the world require dentists to undergo a formal training lasting five to six years, after which they must pass written and practical examinations. Dentistry also requires a high degree of mechanical dexterity because the practice involves using highly sophisticated instruments and materials. The work of a dentist involves not only filling and extracting teeth but also scaling and polishing the teeth to remove tartar, advising on the care of the teeth and gums, designing and supplying false teeth, restoring damaged teeth, and straightening teeth. Additional reading Pierre Fauchard, The Surgeon Dentist: or, Treatise on the Teeth, 2 vol. in 1 (1946, reprinted 1969; originally published in French, 2nd ed., 1746), is a classic work. See also Vincenzo Guerini, A History of Dentistry: From the Most Ancient Times Until the End of the Eighteenth Century (1909, reprinted 1967); and Bernhard Wolf Weinberger, An Introduction to the History of Dentistry, with Medical & Dental Chronology & Bibliographic Data, 2 vol. (1948, reprinted 1981). Malvin E. Ring, Dentistry: An Illustrated History (1985), is a readable comprehensive survey. For a broad range of current information on dentistry, see Dental Abstracts (monthly), a compilation of abstracts of articles from periodicals; and The Year Book of Dentistry, an annual review of selected articles.R.A. Cawson and J.W. Eveson, Oral Pathology and Diagnosis (1987), is a text and colour atlas. Oral and dental surgery is the subject of W. Harry Archer, Oral and Maxillofacial Surgery, 5th ed., 2 vol. (1975); Gustav O. Kruger, Textbook of Oral and Maxillofacial Surgery, 6th ed. (1984); and Daniel M. Laskin (ed.), Oral Surgery (1985). Other dental specialties are covered in John M. Davis, David B. Law, and Thompson M. Lewis, An Atlas of Pedodontics, 2nd ed. (1981); Ralph E. McDonald and David R. Avery (eds.), Dentistry for the Child and Adolescent, 4th ed. (1983); Thomas M. Graber and Brainerd F. Swain, Orthodontics: Current Principles and Techniques (1985); Lee W. Graber (ed.), Orthodontics: State of the Art, Essence of the Science (1986); Louis I. Grossman, Endodontic Practice, 10th ed. (1981); Irving Glickman, Glickman's Clinical Periodontology, 6th ed., edited by Fermin A. Carranza (1984); Henry M. Goldman and D. Walter Cohen, Periodontal Therapy, 6th ed. (1980); Henry M. Goldman et al. (eds.), Current Therapy in Dentistry, 7th ed. (1980); John F. Johnston, Johnston's Modern Practice in Fixed Prosthodontics, 4th ed., edited by Roland W. Dykema, Charles J. Goodacre, and Ralph W. Phillips (1986); Eugene William Skinner, Skinner's Science of Dental Materials, 8th ed., edited by Ralph W. Phillips (1982); Robert G. Craig (ed.), Restorative Dental Materials, 7th ed. (1985); and Frank M. McCarthy (ed.), Emergencies in Dental Practice: Prevention and Treatment, 3rd ed. (1979).Prophylactic measures in dentistry are discussed in Joseph L. Bernier and Joseph C. Muhler (eds.), Improving Dental Practice Through Preventive Measures, 3rd ed. (1975); and Abraham E. Nizel, Nutrition in Preventive Dentistry: Science and Practice, 2nd ed. (1981). David F. Striffler, Wesley O. Young, and Brian A. Burt, Dentistry, Dental Practice, & the Community, 3rd rev. ed. (1983); and James Morse Dunning, Principles of Dental Public Health, 4th ed. (1986), are studies of the relationship between the dentist and society.